package com.bjpowerrnode.javase.date;

import com.sun.source.doctree.SeeTree;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.HashSet;
import java.util.Set;

public class LocalDateTimeTest0 {
    public static void main(String[] args) throws InterruptedException {
        LocalDateTime now = LocalDateTime.now();
        Thread.sleep(3000);
        boolean after = LocalDateTime.now().minusDays(31).isAfter(now);
        System.out.println(after);
        LocalDateTime localDateTime = LocalDateTime.now().minusDays(31);
        DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss SSS");
        System.out.println(dateTimeFormatter.format(localDateTime));

        Set<String> set = new HashSet<>();
        set.add(null);
        set.add(null);
        System.out.println(set.size());

    }
}
